Antidepressant-like effects of two commercially available products of Hypericum perforatum in the forced swim test: A long-term study

Abstract

Some herbal products of Hypericum perforatum (Hypericaceae) are recommended for the treatment of depression. Nevertheless, some of these products do not produce antidepressant-like effects when they are evaluated in experimental models of depression, whereas others remain to be evaluated. Consequently, the antidepressant-like effects of two commercially available products of H. perforatum were evaluated and compared with the clinically effective antidepressant fluoxetine. Male Wistar rats received different doses of two products of H. perforatum or fluoxetine, and their effects were evaluated at 7, 14, 21, and 28 days of treatment in the open field and forced swim tests. H. perforatum products significantly increased the latency to first immobility and reduced total immobility time in the forced swim test, results similar to fluoxetine, without increasing general locomotor activity in the open field test. H. perforatumproducts required 21 days of treatment to exert their antidepressant-like effect, whereas fluoxetine required only 14 days. In conclusion, H. perforatum products evaluated in the present study produced an antidepressant-like effect, even at lower doses than those reported previously to be effective in the forced swim test. However, H. perforatum required more days of treatment to exert its antidepressant-like effect compared with the antidepressant fluoxetine. Key words: Antidepressant, fluoxetine, forced swim test, Hypericaceae,Hypericum perforatum, open field test, rats.